264 University of California Puhlications. [Entomology 



but the great majority were sterile, as was evidenced by their 

 shrinkage in size and the loss of the bright color characteristic 

 of fertile eggs. 



The Larva. — The larva emerges from the egg through an ap- 

 perture of irregular outline across the upper end. For a period 

 of from fifteen minutes to half an hour or more it remains with 

 the body protruding vertically about two-thirds of the way out 

 of the shell, during which time the body becomes hardened suf- 

 ficiently to permit locomotion. At this time the larva is bright 

 yellow in color but gradually assumes the markings characteristic 

 of the species. Twelve to twenty-four hours usually elapse before 

 feeding conunences, the larvae in the meantime remaining 

 grouped upon or in the immediate vicinity of the cluster of 

 broken shells. 



The Pupa. — At the time of discarding the fourth larval skin 

 the pupa is bright yellow in color, but in the course of one to 

 three days, depending upon the conditions of temperature and 

 light, the dark reddish brown base color with the black spots is 

 developed. At the time of emergence the pupal skin breaks at 

 the median line of the thorax and the adult beetle pushes its 

 way out. 



The Adult. — At the time of emergence from the pupal skin 

 the adult is a uniform yellow over the entire surface of the body 

 with the exception of the head, which is black. The natural color 

 appears within the course of a few hours, becoming considerably 

 darker, however, after one or two days. Temperature and light 

 apparently are very strong contributing factors as regards the 

 degree of color development. 



Ovipositiou. — Full records of oviposition were secured of six 

 females taken from cold storage at Sacramento, California, May 

 2, 1913, and of five females reared from pupae collected at Berke- 

 ley, California, during the latter part of March, 1914. Mating 

 took place between beetles from storage from one to ten days 

 later, the average intervening period being 4.5 days. The time 

 elapsing between mating and oviposition varied from eight to 

 thirteen days, with an average for the six specimens of 10.5 days. 



The length of the period of oviposition as determined from 

 eleven individuals varied from 11 to 50 days, averaging 33.3 days. 

 Within these periods the proportion of days upon which eggs 

 were actually deposited extended from 28 to 72.7 per cent, with 

 an average of 63.8 per cent. 



